Rain has brought some welcome relief from the relentless humidity we have been experiencing of late. For the past few days it seems that Autumn has at last made its tardy appearance.  Today’s 5-2 fast day idea is a decadently delicious yet dairy free variation of a classic potato and leek soup. Turning to the sadly depleted contents of my refrigerator following a full house over the weekend,  I substituted gloriously hued in-season  sweet potato for regular potato, added a little freshly grated ginger  for warmth and a tart green granny smith apple for interest and balance.  The result?  Rich, creamy and undeniably delicious.

At just 103 calories per cup serve, it’s another offering that effortlessly falls within the 5-2 restricted calorie brief. The quantities provided make a huge pot of soup. Enough to feed a hungry family or portion out and freeze for a ready fast day meal. The non fasters in our house enjoyed their soup with rustic toasted croutons.  That’s the beauty of soup. It’s infinitely adaptable and  feeds everyone. Easy to prepare, low in calories and deliciously nutritious it’s the perfect cooler weather fast day meal solution. As the temperatures drop I know I will be swapping my fast salads for bowls of steaming soup. Here’s my first offering of the season.

Sweet Potato and Leek Soup With Apple and Ginger
Makes 12 cups ( 103 calories per cup serve)

2 tablespoons olive oil (240 calories)
2 medium leeks, white part only, sliced (74 calories)
3 cloves garlic, crushed (12 calories)
2-3 cm piece fresh ginger, peeled and grated (3 calories)
2 celery ribs, sliced (14 calories)
6 medium sized sweet potatoes, peeled and diced (648 calories)
1 medium granny smith apple, peeled and diced (80 calories)
8 cups (2 litres) vegetable or chicken stock (160 calories)
fresh bay leaf (1 calorie)
sprig of thyme (1 calorie)
sea salt and freshly ground pepper, to season
cayenne pepper, for dusting

HEAT oil in a large saucepan over medium-high heat. Add the leeks with a good pinch of salt. Gently cook, stirring, for 5 minutes or so, until the leeks are soft and transparent. Do not allow them to brown.
ADD the garlic and ginger.  Cook for a minute or so until fragrant, then add the celery, sweet potato and apple. Cook, stirring for a further 5 minutes or so, until the sweet potato and apple begin to soften a little.
ADD the stock, bay leaf and thyme. Bring to the boil. Reduce heat to medium and gently boil, uncovered, for 20 minutes or until potato is cooked. Remove from heat. Discard the thyme and bay, then set aside for 10 minutes to cool.
PUREE soup in batches in the jug of a blender or in the pot with a hand-held immersion stick blender.
REHEAT soup just before serving.  Check seasoning. Adding Ladle the soup among serving bowls. Top with a  very light dusting of  cayenne pepper. Serve immediately.